Electrical apparatus



citizen of the United States of Patented Oct. l3,

um rso STATES PATENT OFFICE.

J'OEI a. man, or Damn, oino, assronoa 'ro DELCO LIGHT COEPANY OF DAYTON, care, a conronn'riozw or nnmwana.

mnrcnnarraaarus. Application am February 24, ms. Serial r earoaa.

To all whom it may concern:

Be it knownthat I, JOHN G. Cmrsnm, a

1 America, resi at Dgton, county of Montgomery, and te of bio, have invented certain new and useful Improvements in Electrical Apparatus, of which the following is a full,

- clear, and exact description.

' This invention relates to speed responsive electrical switches, and has among its objects to provide a simple and compact structure adapted to be' mounted upon the shaft of an electrical machine such as a repulsion induction motor emploving a commutator for starting urposes. Such a switch may be used for s ort circuiting the commutator bars after a certain motor speed has been attained.

Other and further objects and advantages of this invention will be. apparent from the following description of a preferred form thereof, reference being made to the accompanying drawings.

Inthe drawings:

Fig. 1 shows aside elevation of the commutator of a repulsion induction motor and of a short circuiting switch embodying the present invention;

Fig. 2 is a lon 'tudinal sectional view ofparts shown in 1;

' 3 is a sectional view taken on the line 3-3 of Fig. 2; and the section line 2-2 of Fig. 3 denotes the section of Fig. 2.

In the drawings, designates-a fragment of an armature having conductors connected with commutator 21. (/urrentis led to the commutator through brushes in' the well known, manner of repulsion induction m0- tors using a commutator.- One of these brushes is shown at 23 and is supported upon a bracket 24.. Commutator 21 comprises a plurality of bars 22 which are clamped beplanes ofthe longitudinal tween V'rings 25 and 26cooperatingwith screws 27. The commutator is press fitted upon an armature sleeve 28 providedwith driving engagement with motor shaft 29 through a plurality of washers 30 which are provi ed with rectangular holes cooperating with the rectangular portion 31 of shaft 29.

Washers 30 are provided with radiall ex-' tending In 32 which are receiv by notches in t e end of sleeve 28 in order to provide a driving connection between sleeve 28 and the shaft 29. i

The speed responsive switch comprises a hub 40 mounted on the reduced cylindrical end 35 of shaft 29. A hub in position. Hub 40 is attached to a late 41 provided with portions 42 bent 0biquel with respect to the mainportion of the p ate 41 in orderto provide wedging surfaces 43 which are preferably equally spaced as shown in Fig. 3. Studs 44 are riveted to plate 41, and unon these studs are slidably mounted, axially of shaft 29, a switch contact member 45 and a disc 46 having portions 47 providing wedgin surfaces 48, each surface 48 being located'opposite a wed ging surface 43 of plate 41 and obliquely inclinedwith respect theretoi A spring 49 presses at one end against the parts 30 and at the other against the contact member 45, causing it to be separated from the commu- 'tator 21 and the plate 46 to be pressed to; ward the plate 41 and a plurality of balls 50 to be engaged by ad'acent parallel surfaces ofthe plates 41 an 4 The balls 50 are located within apertuies 51 provided in weight members 52 hich are pivotally mounted upon the studs 44.

nut 36 maintains the When a certain speed has been attained by in Figs. 1 and 2 -so that switch contact- 45 may be pressed against the end of the commutator 21 toshort circuit the commutator bars. The'motor will then operat'e as a simple induction motor for reasons well known to those skilled in the-art.

- When the motor stops the spring 49 will return the balls 50 and weights 52 to the position shown in the draw By removing nut 36, the switch mechanism ma be removed as a unit from the shaft wit out disturbing other parts mounted thereon.

It is understood, however, that this invention is susceptible of other uses, and espe-v cially where the switch or circuit breaking mechanism is adapted to be located partly or wholly upon a rotating shaft.

While the form of mechanism herein shown and described constitutes a preferred embodiment of one form of invention, it is to be understood that other forms might be p msmb adopted and various chan and alterations made in the shape, size, and proportion of the elements therein without departing from the spirit and scope of tion, Ii-3?? What-is claimed is as follows:

1. A commutator short-circuiting device for an electric motor .com rising, m combination,- .a rotatable m r including a X late carried by the rotatable member and ocated adjacent the commutator of the motor, a second plate longitudinally movable with respect to'the sha of the motor, one 0t be rovidedwithbaicammmg ace; a we t interposed ween said plates and pivotally mounted upon said weigh d ada gd ed l t an e to oneo sai platesandthecammingsurfaceoftheother -plateformovin said movable ,anda contact 0 by the movab plate for '1 thebarsofthecommutator.

A commutator short-circuiting device for an electljgumobtfr com rising,lin combmatxon, a ta e m inc udmg' a mrried by the rotatable member and I adjacent the commutator of the motor a second plate 1 'tudinally movable wi respect to the of the motor, one

a a m r a said aperture and adaptedtooneofsaidplates andthecamming surface of'the other plate for movin said movable plate, and a contact 0 ref e ivo ger, weight ha late carried by the rotatable member and coated adjacent the commutator of the motor, a second plate 10 'tudinally movable with respect to the sha of the motor said plates being provided with oppositely-inclined wedgmg surfaces adjacent each other a weight interposed between said platesand ivotally mounted upon said rotatable memr, a member earned by said t and adapted to engage said wedging su aces for said movable filate, and a ogerated b the movab late for t e bars of the commutat r. I 4. A commutator device foranelectricmotorcomrisingmcom-r bination, a rotatable m including a late carried by the rotatable member and coated adjacent the commutator of the mo- ,tor' afksecond plate'fl 'tudinally movable with-tespect-to the an of a motor said provided with oppositely-ina we ft-interposed between said plates .mounted upon said rotatable mem- 111 d Mmcarnedmtliinsaid Y I infisurfaces for n lovinisai movable plate, an a contact operated y the movable plate for engaging the bars of the commutator.

- In testimony whereof I hereto aflix my signa' ture. a

' JOHNG. CAMPBELL.

suriacesadjacenteachother anapertureextend- I 

